Skip to Main content Skip to Navigation
Journal articles

Revisiting a Disky Origin for the Faint Branch of the Sagittarius Stellar Stream

Abstract : We investigate ways to produce the bifurcation observed in the stellar stream of the Sagittarius dwarf galaxy (Sgr). Our method consists of running N-body simulations of Sgr falling into the Milky Way for the last 3 Gyr, with added test particles on disk orbits that span a wide range of initial positions, energies, and angular momenta. We find that particles that end up in the faint branch are predominantly high-angular-momentum particles that can all originate from a single plane within the progenitor, nearly perpendicular both to the orbital plane of the progenitor and to the Milky Way stellar disk. Their original configuration at the start of the simulation corresponds to spiral features already present 3 Gyr ago, which could be, e.g., the result of a disk-like component being tidally perturbed, or the tidal tails of a satellite being disrupted within Sgr. We then run a simulation including the self-gravity of this disky component. Despite the remaining ambiguity of its origin, this disk component of the Sgr dwarf with spiral overdensities provides a first step toward a working model to reproduce the observed faint branch of the bifurcated Sgr stream.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03705582
Contributor : Olivier Hauss Connect in order to contact the contributor
Submitted on : Monday, June 27, 2022 - 10:55:01 AM
Last modification on : Tuesday, June 28, 2022 - 3:33:50 AM

Links full text

Identifiers

Collections

Citation

Pierre-Antoine Oria, Rodrigo Ibata, Pau Ramos, Benoit Famaey, Raphaël Errani. Revisiting a Disky Origin for the Faint Branch of the Sagittarius Stellar Stream. The Astrophysical Journal Letters, 2022, 932, ⟨10.3847/2041-8213/ac738c⟩. ⟨insu-03705582⟩

Share

Metrics

Record views

0